Non-erasable optical data storage memories have been recently introduced to the memory market. In the case of a compact disk, PCM signals (Pulse Code Modulated Signals) are embossed directly into a polymer substrate. This is done using an injection molding process by using a special mold which transfers microscopically small pits into the disk surface. The pitted surface is coated with a thin reflective material such as aluminum. The information on the disk is read out using a low energy laser. The laser irradiates the polymer side of the disk. The polymer is transparent. The laser reflects off the reflective surface. The Sequence of reflection and non-reflection caused by pit sequence on the disk surface is used as a binary code to store information.
A sensor, such as a photodiode, detects the reflected light from the pattern. An electrical signal generated in the detector is monitored to thereby permit reading of the data stored on the disk.
According to the present invention an optical storage device is fabricated from a polymeric material. Oxide particles are selectively formed in regions of a polymeric film on the surface of an optically reflecting substrate. The regions of the film having the oxide particles therein have a different reflectivity than those regions of the polymeric film which do not have the oxide particles therein. By scanning an optical beam across the pattern of oxide particles the reflected light can be monitored permitting data stored in the pattern sequence to be read.
It is an object of this invention to provide a polymeric material having a pattern of oxide particles therein.
It is an object of this invention to provide an optical storage device having a pattern of oxide particles embedded in a polymeric material as the optical storage medium.
It is another object of this invention to provide an optical storage device having a pattern of metal oxide particles embedded in a polymeric material.
It is another object of this invention to provide an optical storage device having a pattern of copper oxide particles embedded in a polymeric material.
It is another object of this invention to provide a method for fabricating an optical storage device using a polymeric material with a pattern of oxide particles embedded therein.
It is another object of this invention to provide an optical storage device using a polymeric material as the optical storage medium wherein the polymeric material is a polyamic acid metal complex with regions of polyimide having oxide particles embedded therein.